124 research outputs found
El sitio fortificado del Castelinho (Felgar, Torre de Moncorvo, Portugal). Estudio preliminar de su diacronía y las plaquetas de piedra con grabados de la Edad del Hierro
In this text we present the results of the first archeological intervention in the Iron Age site of Castelinho. The uniquenessof the site, demonstrated by the presence of structures as well as an impressive assemblage of engraved stone plaquettes,has made the site difficult to characterize considering the regional context. The site, situated on a high point withcommanding view of the surrounding area and enclosed by a massive “defensive system” of ditches and walls, could beconsidered as a Hillfort (castro) in the classic sense of the word. After a year of archaeological work in this importantsite we will address here several hypotheses in connection to the diachronic evolution of the hillfort, and the exceptionalcollection of portable art unearthed.Se presentan los resultados de la excavación arqueológica llevada a cabo en el sitio fortificado de la Edad del Hierrode Castelinho. La excepcionalidad del lugar, representada por las estructuras que posee y el extraordinario conjunto deplaquetas de piedra con grabados recientemente descubierto, ha tornado difícil su caracterización dentro del conjuntode la Edad del Hierro. Por las particularidades que el sitio presenta, situado en altura y con un amplio dominio visual,dotado de un imponente “sistema defensivo” con fosos y murallas asociados, podría considerarse como un castro en elsentido clásico del término. Tras un año de trabajos en esta importante estación arqueológica transmontana, se ofrecenen este artículo las primeras hipótesis en relación a su evolución diacrónica y la colección excepcional de arte mueble
O Sítio e a Laje 1 do Castelinho (Cilhades, Felgar, Torre de Moncorvo). Contributos para o conhecimento da II Idade do Ferro em Trás-os-Montes Oriental
info:eu-repo/semantics/publishedVersio
CRÔNICAS DO ESTADO NOVO: GRACILIANO RAMOS E A REVISTA CULTURA POLÍTICA
As crônicas publicadas por Graciliano Ramos e reunidas postumamente em dois livros Linhas tortas e Viventes das Alagoas são a viga mestra da investigação deste artigo. O escritor alagoano se serviu do gênero cronístico em três momentos distintos. Primeiro como laboratório literário na sua primeira viagem ao Rio de Janeiro, depois na sua volta a Alagoas e por fim quando dela se serve como meio de sobrevivência. Em Viventes das Alagoas aparecem os textos produzidos para a revista Cultura Política, publicação subordinada ao Departamento de Imprensa e Propaganda da ditadura Vargas. Averiguou-se essa agência e seu papel, além de perquirir as circunstâncias que levaram Graciliano Ramos a colaborar por quatro anos em um Aparelho Ideológico do Estado, regime que o encarcerou. Para alguns estudiosos, necessidade econômica, para outros, alinhamento político-ideológico. Detectou-se a ironia e o tom acrimonioso que desconstruía o projeto de nacionalidade estado-novista e, portanto, esvaziam-se as insinuações de emparelhamento do escritor ao projeto cultural da revista
Urea-based polymethacrylamide purification
A purification procedure of polymethacrylamide (PMAm) based on the urea feature of being a powerful Hbondbreaker is proposed here. Polymethacrylamide was synthesized in water and the final product presentsitself as an insoluble gel what is an obstacle to purification. This physical gel, kept together by numerousinterchain H-bonds between amide groups in the polymer, is dismantle by a urea solution (4 mol.L-1) makingthe polymer soluble. Methanol is then used to precipitate the polymer, keeping urea, water and methacrylamidein the methanolic phase.FTIR, TGA, GPC and HPLC were used to characterize the final product and to prove the efficiency and convenienceof this method. The procedure proposed here has presented a good recovery of the polymer and canbe considered more convenient, less time-consuming and efficient than others such as dialysis.Keywords: Physical Gel, Polymethacrylamide, Polymer Purification, Urea
El sitio fortificado del Castelinho (Felgar, Torre de Moncorvo, Portugal). Estudio preliminar de su diacronía y las plaquetas de piedra con grabados de la Edad del Hierro
info:eu-repo/semantics/publishedVersio
Atributos do solo em sistemas de cultivo irrigado agroecológico e convencional no Semiárido do Rio Grande do Norte
A sustentabilidade dos sistemas agrícolas irrigados na região semiárida passa pela manutenção da capacidade produtiva. O objetivo desse trabalho foi avaliar a qualidade do solo em áreas irrigadas agroecológica e convencional, localizadas na comunidade de Sombras Grandes, Caraúbas, Rio Grande do Norte. Foram coletadas amostras simples de solo (0-20 cm e 20-40 cm) de 2009 a 2012. Utilizaram-se indicadores: físicos: densidade do solo (Ds), porosidade total (PT), resistência à penetração (RP), relação de água disponível e porosidade total (AD/PT), relação da umidade volumétrica na capacidade de campo e a porosidade total (Uvcc/PT), grau de floculação (GF) e argila dispersa em água (ADA); químicos: pH, fósforo (P), capacidade de troca catiônica (CTC), saturação de bases (V), soma de bases (SB), carbono orgânico total (COT), estoque de carbono (Est C), cálcio (Ca+2), magnésio (Mg+2), potássio (K+), sódio (Na+), (percentagem de sódio trocável) PST e condutividade elétrica (CE). O teste não paramétrico de Kruskal Wallis, a correlação de Pearson e a análise de componentes principais foram usados para avaliar a qualidade do solo. A SB apresentou correlação significante e positiva na área agroecológica com V, COT e CTC e na área convencional com V e CTC. A Ds, PT, ADA e GF, COT e Al + H diferiram significativamente e melhores resultados de qualidade do solo foram verificados na área agroecológica (0-20 cm). O Ca+2, Mg+2, K+, CTC, P e SB não foram diferentes e os valores altos verificados mantiveram a fertilidade do solo em ambas as áreas estudadas. A capacidade produtiva do solo é mantida na área agroecológica, sem aplicação de adubos químicos sintéticos
Aging, neurocognitive impairment and adherence to antiretroviral therapy in human immunodeficiency virus-infected individuals
AbstractBackground/objectiveThere is an increasing number of older patients with human immunodeficiency virus infection due to the success of antiretroviral therapy, the improved prognosis and life expectancy of patients, and the higher number of new infections among older individuals. The main objective of the present study was to compare the characteristics of older human immunodeficiency virus patients with those of younger patients.Materials and methodsWe conducted a cross-sectional study with human immunodeficiency virus-infected patients who were treated at the Specialized Care Service (Serviço de Assistência Especializada) for human immunodeficiency virus/AIDS in the city of Pelotas, South Brazil. Sociodemographic information as well as data on human immunodeficiency virus infection and treatment were collected. All participants underwent psychiatric and neurocognitive assessments, and their adherence to antiretroviral therapy was evaluated.ResultsA total of 392 patients participated in the study, with 114 patients aged 50 years and older. The characteristics showing significant differences between older and younger human immunodeficiency virus-infected patients included race/ethnicity, comorbidities, duration and adherence to antiretroviral therapy, currently undetectable viral load, and cognitive impairment. Compared to younger patients, older patients were at higher risk of exhibiting cognitive impairment [OR 2.28 (95% CI: 1.35–3.82, p=0.002)] and of having increased adherence to antiretroviral therapy [OR 3.11 (95% CI: 1.67–5.79, p<0.001)].ConclusionsThe prevalence of neurocognitive impairment remained high in human immunodeficiency virus-infected patients despite antiretroviral therapy. In the present study, the prevalence of this type of impairment was significantly higher in patients aged ≥50 years, most likely due to aging, human immunodeficiency virus infection, and a possible synergistic effect between these factors. Despite this higher prevalence, older patients exhibited higher rates of adherence to antiretroviral therapy and of undetectable human immunodeficiency virus viral load
Soil preparation and NPK fertilization in the planting of five Atlantic Rainforest species in a clay extraction area
The occurrence of degraded areas worldwide grows each year and measures must be taken to mitigate degradation and to recover these areas. The aim of this study was to assess the effect of soil preparation and NPK levels on the growth of five native species of the Atlantic Rainforest in clay extraction area. The experimental design was randomized block in a split-split plot arrangement with four replications. Subsoiling and scarification soil preparation represented main plots. Doses of NPK 04-14-08: 0; 40; 80;160; and 320 g pit-1 represented subplots and Atlantic Rainforest native species represented sub-subplots. Absolute growth rate, stem diameter and number of leaves were evaluated, 210 days after planting. The type of soil preparation did not influence the development of the species. The best dose for Dalbergia ecastaphyllum, Inga laurina, Protium heptaphyllum and Psidium cattleyanum were 176.49, 150.18, 199.25 and 166.48 g pit-1 of NPK, respectively. Schinus terebinthifolius was highly responsive to planting fertilization, being recommended 320 g pit-1 of NPK. All species are indicated for area recovery.The occurrence of degraded areas worldwide grows each year and measures must be taken to mitigate degradation and to recover these areas. The aim of this study was to assess the effect of soil preparation and NPK levels on the growth of five native species of the Atlantic Rainforest in clay extraction area. The experimental design was randomized block in a split-split plot arrangement with four replications. Subsoiling and scarification soil preparation represented main plots. Doses of NPK 04-14-08: 0; 40; 80;160; and 320 g pit-1 represented subplots and Atlantic Rainforest native species represented sub-subplots. Absolute growth rate, stem diameter and number of leaves were evaluated, 210 days after planting. The type of soil preparation did not influence the development of the species. The best dose for Dalbergia ecastaphyllum, Inga laurina, Protium heptaphyllum and Psidium cattleyanum were 176.49, 150.18, 199.25 and 166.48 g pit-1 of NPK, respectively. Schinus terebinthifolius was highly responsive to planting fertilization, being recommended 320 g pit-1 of NPK. All species are indicated for area recovery
Influencia de las características del neumático de la performance del tractor
La presión, el patinaje y el tipo de construcción del neumático son factores significativos para el desempeño del tractor. Este trabajo tiene como objetivo recoger informaciones sobre la influencia de diferentes lastrajes, presiones, construcciones de neumático y diferentes superficies en el desempeño del tractor. La utilización de ciertas de presiones de inflado, y ciertos niveles de lastrajes posibilita obtener un mayor rendimiento del tractor, reduciendo perdidas de energía por la resistencia al rodamiento, reduciendo también perdida de tracción, patinaje y consumo de combustible. La interacción entre un neumático y el suelo varia conforme la superficie de rodamiento, impactando en el rendimiento operacional de los tractores. Se puede concluir que el desempeño de un tractor agrícola depende de condiciones como presión en los neumáticos, tipos de construcción de los neumáticos, patinaje y lastraje. El uso de neumáticos con mayores presiones acarrea mayor compactación del suelo.The pressure, slippage and type of tire construction are significant factors for a tractor’s performance. This work aims to gather information about the influence of different ballast levels, pressures, tire constructions and different surfaces on the tractor’s performance. The use of certain inflation pressures and ballast levels makes it possible to achieve a higher tractor operational efficiency, reducing energy losses by rolling resistance, also reducing the loss of traction, slippage and fuel consumption. The interaction between tire and soil varies according to the rolling surface, affecting the tractor’s operational performance. It can be concluded that the performance of an agricultural tractor depends on conditions such as tire pressure, tire building types, slip and ballasting. The use of tires with higher pressure causes greater soil compaction.A pressão, patinagem e o tipo de construção do pneu são fatores significativos para o desempenho do trator. Este trabalho tem como objetivo recolher informações sobre a influência de diferentes lastragens, pressões, construções de pneu e diferentes superfícies no desempenho do trator. A utilização de certas de pressões de insuflagem, e certos níveis de lastragem possibilita obter um maior rendimento do trator, reduzindo perdas de energia pela resistência ao rolamento, reduzindo também perda de tração, patinagem e consumo de combustível. A interação entre o pneu e o solo varia conforme a superfície de rolamento, impactando no rendimento operacional dos tratores. Pode-se concluir que o desempenho de um trator agrícola depende de condições como pressão nos pneus, tipos de construção dos pneus, patinagem e lastragem. O uso de pneus com maiores pressões acarreta maior compactação do solo
Analysis of the Chemical Modification of Dental Enamel Submitted to 35% Hydrogen Peroxide “In-Office” Whitening, with or without Calcium
Purpose. The purpose of this study was to evaluate changes in calcium and phosphorus content in dental enamel when subjected to “in-office” whitening for an extended time by using a 35% hydrogen peroxide solution, with and without calcium. Materials and Methods. 10 human teeth, from which the roots had been removed, were embedded in epoxy resin, and their surfaces were smoothed. The specimens were divided into two groups; in group 1, a whitening solution without calcium was used, while in group 2, the solution included calcium. Each specimen was evaluated at 6 different points before the bleaching treatment, and these points were reassessed after each session. A total of five sessions were carried out. Concentrations of calcium and phosphorus were measured by using the technique of X-ray fluorescence. Results. After performing a statistical analysis, it was found that there was no statistically significant loss of calcium and phosphorus during the whitening treatment, and the groups showed no statistical differences. Conclusion. Excessive use of hydrogen peroxide, with or without calcium, causes no loss of calcium and phosphorus
- …